Most people feel happy and energized on some days and less so on others. But if these mood changes last for a week or more and are severe—making it hard for you to sleep, stay focused or go to work—it may be a sign of bipolar disorder. Read more about bipolar disorder.

It can happen any time and any place. A stroke can come on suddenly, and its effects can be devastating. The good news is that you can halt the brain damage caused by a stroke if you act quickly. That’s why it’s important to know the warning signs of stroke, and to get help right away if you see them.
Read more about stroke.